Transformer and method of cooling same



(No Model.) 3 Sheets-Sheet 1.

W. S. MOODY. TRANSFORMER AND METHOD OF COOLING SAME. I No. 558,090. Patented Apr. 14, 1896.

(No Model.) 3 Sheets-Sheet 2.

W. s. MOODY. TRANSFORMER AND METHOD OF COOLING SAME. No. 558,090.. Patented Apr. 14, 1896'.

AN DREW BYGRAHAM. PHOTOUTHO WASHINGYUKD C (No Model.) 3 Sheets-Sheet 3.

W. s. MOODY. TRANSFORMER AND METHOD OF COOLING SAME.

No. 558,090. Patented Apr. 14, 1896.

UNITED STATES PATENT OFFICE.

IVALTER S. MOODY, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THE GENERAL ELECTRIC COMPANY, OF NElV YORK.

TRANSFORMER AND METHOD OF COOLING SAME.

SPECIFICATION forming part of Letters Patent No. 558,090, dated April 14, 1896.

Application filed January 17, 1896- Serial No. 575,827. (No model.)

,To ctZZ whom it may concern:

Be it known that I, WALTER S. MOODY, a citizen of the United States, residing at Lynn, in the county of Essex, State of Massachusetts, have invented certain new and useful Improvements in Transformers and Methods of Cooling the Same, (Case No. 265,) of which the following is a specification.

The object of the present invention is to make use of an oil or other insulating circulation in a novel manner, and at the same time to do away with the usual expensive inclosing-tank.

W'ith transformers of a very large size it is necessary to provide some means, such as an oil circulation, for lowering the temperature in order to reduce the loss of energy due to heating. This I accomplish by constructing the transformer-core in such a manner as toform a practically fluid-tight casing with chambers extending in an upward direction from the base to the top. In these chambers are placed the coils of wire forming the primary and secondary windings and supported in their respective places by means of insulating-blocks. Passages are left between the coils, and the blocks separating the coils from the core are provided with grooves, which also form passages. These extend from a chamber in the base to the top of the transformer, where a flange is provided for maintaining a head of oil, with means for distributing the oil in an even fiow down the outside.

In the base of the transformer is a suitable chamber connected with a source of oil supply and with the upwardly-extending passages. The oil on entering the base is forced upward through the passages by a pump or other suitable means at a rate sufficient to absord the heat generated by the coils. On overflowing the flange at the top it is allowed to flow down over the sides of the transformer in a thin film, which serves to cool it to a greater or less extent. If the surface over which the oil is allowed to flow is extended or it is subjected to streams of cold air, it will not be necessary to provide other cooling means; but if these are omitted it will be necessary to pass the oil through coolingtanks or coils of pipe.

dust, it is well to put a dust-proof case over 7 it in order to keep the oil free from impurities. If a number are to be used, it is best to build a separate house for them, and in that case no dust-covers would be used. Preferably in a case of this kind an air circulation would be used in connection with the oil, and in using this the air should be filtered to free it from all particles of dust, &c.

In the drawings, Figure 1 is a Vertical section of the transformer on the line 1 1 of Fig. 2. Fig. 2 is a View in cross-section taken on the line 2 2 of Fig. 1. Fig. 3 is a diagram representing the positions and connections of the cooling apparatus as applied to one or more such transformers, and Fig. 4 shows a transformer-house with the transformers and cooling appliances arranged according to the present invention.

In Fig. 1,P P and S S represent, respectively, the primary and secondary conductors of a large-sized transformer, one capable of deliverin g several thousand kilowatts, the number of turns of the primary and secondary conductors being proportioned to receive and deliver alternating currents of the desired potentials. These primary and secondary conductors have iron laminae built up around them in a com pact mass in the usual manner and are maintained at suitable distances from each other and from the iron core by insulating spacing blocks or plugs, as indicated in Fig. 2. These spaces are so arranged that they constitute vertical channels extending from the bottom to the top.

The laminae of the transformers are held together by means of upper and lower caps 7a, which are bolted together by bolts a. The cap 70 is provided with a flange 71: which is fitted to the base B in such a manner as to make a fairly tight joint. The upper cap has a flange lei-which projects upward in' such a manner as to form a receptacle for the oil. The oil flowing through the grooves 7t and down the sides of the flange is received in a small catch-basin b. The edge of the flange 79 and the outside edge of the catch-basin b are provided with. grooves or notches 70 70" to prevent the oil from running over the edge at any one point, which would be the case if the edges were smooth and the transformer was not perfectly level. The metal between the grooves tends to keep a slight head of oil, thus allowing an approximately equal amount to flow down the sides of the transformer at all points. Small holes bored in the flanges or any other means of restricting the flow of oil at one point so as to insure a flow at the higher points in case the transformer is not standing exactly level suffice for the same purpose.

The base 13 is provided with a chamber C, to which is connected an inlet-pipe c. The .flange K fitting closely into its seat forms the balance of the chamber, which is filled with an insulating fluid, such as paraffin-oil, of high boiling-point. The base I3 is also provided with a catch-basin D extending all the way around, and this channel communicates with the small chamber 0 also formed in the base B, and from which leads a pipe 0, serving to convey the oil from the transformer.

The direction of flow of the cooling fluid is indicated by the arrows. It enters by the pipe 0, flows up through the spaces between the coils and between the coils and core, and at last, overflowing through the notches 7t and passes to the outside of the transformer, whence it flows over the exterior surface of the same in streams and is collected in the catch-basin D, and then flows to the chamber 0 and afterward out to the external pipe system.

The laminre, being assembled in the manner described, form a practically fluid-tight casing, and while the greater portion of the oil would flow up through the vertical pas sages and down the outside a certain amount flows through the spaces between the laminze in a transverse direction to the main body of oil. The oil flowing outward from the cen ter in this manner tends to cool the laminze at this point, and the amount of flow maybe regulated by adjusting the'pressure between the laminae.

It will be observed that the transformer is not, as has hitherto been the case, entirely immersed in a vessel filled with oil, but that the oil simply flows up through its interior and down its exterior, the circulation being maintained in any suitable way and at such a rate as serves to abstract all the heat necessary for the safe and economical working of the apparatus.

A casing His shown in dotted lines, and while this casing would ordinarily be employed in case the transformers were installed in a station along with other apparatus or in situations where dust or dirt abounded it is much preferred, especially where a number of such transformers are to be installed, to erect a separate structure or providea separate room for the transformers, and in this event the casing II is not used, but the transformer is left open to the air.

Fig. 2 shows the mode of supporting the conductors and insulating them from each other. The wooden spacing-blocks d d separate the coils from each other, but leave open passages ff between them for the circulation of the oil. The wooden spacing-blocks d (1' separate the conductors from the iron core and insulate them therefrom. These blocks have grooves upon opposite sides, as indicated, the outer one'serving as a support and guide for the conductors and the inner one serving to form a channel for the circulation of oil in contact with the iron core.

The circulation of the oil is readily maintained by a pump 6, Fig. 3, driven by any suitable motor M, which lifts the oil from the reservoir B after it comes from the trans former T and forces it through a coil of pipe having an extended surface in contact with water or air, where it is cooled, after which it passes to the elevated reservoir R and flows by gravity again to the transformer.

In Fig. 4: F is a transformer house or room containing six large transformers like those shown in Fig. 1, but having the casing omitted. The reservoir R supplies all the transformers T to T with cooled oil through the distributing-pipes I I, and the oil is returned through the pipes I I, valves being provided for shutting off the supply to the individual transformers.

So far as I am aware, Iam the first to lower the temperature of the transformers by maintainin g a body of oil in the interior thereof and allowing it to flow down the out-side in a free and unobstructed manner.

IVhile my invention is specially applicable to transformers, its application extends to any other electrical apparatus.

hat I claim as new, and desire to secure by Letters Patent of the United States, is

1. In a transformer, the combination of coils of wire surrounded by an iron core, and an insulating medium flowing down the outside of the core in a film.

2. In a transformer, the combination of coils surrounded by an iron core, spaces in the core, and means for maintaining an upward oil circulation through the spaces.

3. In a transformer, the combination of coils surrounded by an iron core, spaces in the core, an upward oil circulation, and means for carrying the oil to the outside of the core and allowing it to flow down.

at. In a transformer, the combination of coils surrounded by an iron core, spaces between the coils and the core and between each other, the spaces forming up-and-down passages, an oil circulation flowing through these passages, and means at the top for distributing the oil down the outside of the core in an even flow.

5. In a transformer, the combination of a core forming a practically fluid-tight casing, coils surrounded by the core and separated therefrom by up-and-down passages extending through the transformer, a cap provided with a flange at the top maintaining a head of oil, and grooves for distributing the oil in a film down the outside of the core.

(3. In a transformer, the combination of coils surrounded by a core forming a practically fluid-tight casing, with a forced circulation of fluid through openings in the interior of the transformer.

7. In a transformer, a main up-and-down circulation of oil, and a circulation transverse thereto.

8. In a transformer, the combination of upand-down passages with oil circulating therein, with transverse passages between the laminse and a limited circulation therein.

9. In a transformer, the combination of primary and secondary coils, an iron core forming practically a fluid-tight casing, a main oil circulation having an up-and-down direction, and a limited circulation in a direction transverse thereto.

10. In a transformer, the combination of oil-passages extending through the laminze, with a cap provided with means for evenly distributing the flow of oil down the sides.

11. The combination in a transformer, of primary and secondary coils, a laminated core surrounding the coils, a number of passages through the interior of the transformer, and means for maintaining an upward circulation of an insulating fluid, as oil, through said passages, and conveying the oil so that it runs down the outside of the core.

12. In a transformer, the combination of oil-passages extending upward from the base, a cap formed with a flange to maintain a head of oil, and grooves cut in the top of the flange to insure an even distribution of the oil down the sides of the transformer.

13. In a transformer, the combination of a base having a chamber connecting with the passages extending through the laminze, a cap provided with a flange and a catch-basin, the latter extending to the edge of the laminae and regulating the flow of oil down the sides of the transformer.

1i. In a transformer, the combination of a receiving-chamber in the base, passages ex tending through the laminze, a flange forming a receptacle for the head of oil, a catch-basin at the top of the transformer to distribute the oil, and a second catch-basin to receive the oil, formed integral with the base and connecting with an outlet-chamber also located in the base.

15. In a transformer system, the combination of means for cooling the oil, a reservoir for maintaining a head of oil, a connection between the reservoir and the chamber in the base of the transformer and the passages eX- tending upward through the laminae, a cap provided with means forholding a body of oil at the top of the transformer, means for insuring an even distribution of oil down the sides thereof, a catch-basin located at the base to receive the oil as it flows down the sides of the transformer, and a pump to effect the circulation.

16. In a transformer, the combination of primary and secondary coils, a base provided with a chamber, channels between the coils connected with the chamber in the base, and forming a passage for an insulating fluid.

17. In a transformer, the combination of top and bottom caps between which the laminae are clamped, a base adapted to receive the bottom cap, and passages between the different coils and between the coils and the lamina, forming channels to receive an insulating fluid.

18. In a transformer, the combination of primary and secondary coils, laminae surrounding the coils, insulating-blocks between the several coils and the core, channels cut in the blocks forming passages for the insulating fluid, other blocks separating the coils and forming a second set of passages, abase having a chamber connecting with the passages, and a top provided with a flange to maintain a head of oil sufficient to cover the coils.

19. In a transformer system, the combination of electric coils in inductive relation to each other, lamina: surrounding the coils, passages between the several coils and the core, and a pump to maintain a circulation through the interior of the transformer.

20. I11 a transformer system, the combination of electric coils surrounded by laminae separated therefrom and from each other, by oil-passages, and means for circulating the oil through these passages under pressure.

21. In a transformer, the combination of primary and secondary coils, a core surrounding the coils, passages in the core, and an insulatin g compound supplied to these passages under pressure and allowed to flow down the sides of the transformer in an unobstructed manner.

22. In a transformer, the combination of coils surrounded by a practically fluid-tight core, means for forcing oil upward through passages formed in the core, and an extended surface over which the oil flows for the purpose of cooling the same.

In witness whereof I have hereunto set my hand this 14th day of January, 1896.

WALTER S. MOODY. lVitnesses JOHN W. GIBBONEY,

HENRY M. HOBART. 

